Nokia M11 T66220, User Manual

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Applications and features
E
Copyright Nokia Networks Oy C33833001SE_00
2-7
Payload encapsulations
Both routed and bridged protocols are encapsulated in the ATM link by
using either RFC 1483 LLC/SNAP encapsulation or VC multiplexing.
M11 also supports PPP over AAL5 encapsulation, in which both
bridged and routed protocols are first encapsulated in PPP (RFC 1661).
PPP is then encapsulated in ATM according to the IETF PPP over
AAL5 using RFC 2364 VC multiplexing or LLC/NLPID
encapsulation.
See Chapter 6 for more information on the payload encapsulations.
Transmit priority selection
If you are using more than one upstream connections, you can set
priorities to these connections. You can also set the maximum transmit
rate to the connection. The following example explains the transmit
priority selection:
Connection Priority Maximum transmit
rate
VCC1 HIGH 400 kbit/s
VCC2 LOW 0 (no limit)
Table 2-1 Transmit priority selection example settings
The settings shown in Table 2-1 affect the connections in the following
way:
D
When VCC1 is not transmitting, VCC2 can use the whole
bandwidth.
D
When VCC2 is not transmitting, VCC1 gets only 400 kbit/s even if
there was more bandwidth available on the upstream link.
D
When VCC1 starts transmitting, it gets 400 kbit/s bandwidth and
VCC2 gets the rest of the available bandwidth.
D
If the upstream bandwidth is 400 kbit/s and VCC1 uses 400 kbit/s,
VCC2 can not transmit anything until VCC1 starts to transmit less
than 400 kbit/s.
IGMP proxy function
M11 can be used as an IGMP proxy which means that M11 can send
IGMP queries and have IP hosts report their IP multicast host group
memberships. See Chapter 6 for more information about IP multicast.